The subject matter disclosed herein relates to an optical enhancing device, such as a telescopic observation sighting device or individual shoulder (or hand-fired) firearms sighting device (telescopic sight herein). Embodiments according to the subject matter disclosed herein may also be used with any optical enhancing device containing adjusters, such as a microscope, telescope, etc. For purposes of illustration, it will be assumed herein that the optical enhancing device is a telescopic firearms sight.
A telescopic sight, typically used to aim a firearm, is usually mounted on the firearm. An adjustment knob on a telescopic sight is typically used for changing a setting of an adjuster, for example, elevation, crossrange (also “windage” herein), or parallax, of the telescopic sight. Parameters such as elevation, crossrange, and parallax, may be painstakingly set in order that the projectile fired from the firearm hit a specific target. Once set for a particular target parameter, the setting preferably remains unchanged until after a shot is fired at the target.
Existing telescopic sighting systems for civilian, law enforcement, and military firearms typically utilize two types of adjustment knobs. The first type of adjustment knob is allowed to rotate freely. The knob is permanently exposed, or is uncovered by removing a cover cap to make an adjustment. The second type of knob is a locking knob in which the lock must be released prior to making an adjustment. Around the circumference of both types of knobs are numerals and index marks to indicate the rotational setting of the knob with respect to a fixed datum mark. To adjust the knob of the telescopic sight so that the projectile impacts the target at a known distance requires an operator to visually check the reference marks against the datum mark to verify the settings are correct. In some circumstances, such as a military or tactical application in which the telescopic sight is used in the dark, the operator cannot visually check the telescopic sight setting.